My invention relates to a route interlocking control system for railroads. More specifically, the invention relates to a system in which a single route request relay controls both directions of traffic through a railroad interlocking along each possible track route and a single route locking relay for each entrance location to the interlocking locks up each possible route originating at that entry point, when established, and selects and enables the clearing of the proper entry signal.
In developing interlocking control systems for rapid transit railroads, it is desirable to reduce the operations required of the system operator in controlling the routing of trains. Thus a route type interlocking control system, requiring the operation of only one selector or circuit controller device to establish each route, is preferable. It is also desirable to use a minimum amount of apparatus in any interlocking control system. In other words, a specific route interlocking system should be designed to use the fewest number of relays possible to accomplish the stated purpose and provide all specified features. One possible manner of conserving relays in such a system is to use only one relay to request and initiate the establishment of traffic in either direction over each possible track route or lineup through the interlocking. A second possible point of saving is to use a single relay to lock all possible routes originating from a specific entry point when requested and aligned and to also control or enable the selection and clearing of the entry signal at the established entrance end of the lined route. By accomplishing these two points, additional savings are then possible in the apparatus involved in the various indication circuits and secondary control networks.
Accordingly, an object of my invention is an improved interlocking control system for rapid transit railroads.
Another object of the invention is a route interlocking control system using only one route request relay for establishing either direction of traffic along each possible track route through an interlocking layout.
Still another object of the invention is a control system for a railroad interlocking requiring only a single push button to select each desired route and a single relay to register a request for the desired route or at other times for the identical opposite route through the track layout.
A further object of my invention is an improved railroad route interlocking control system using a single route request relay for either traffic direction along each possible track route through the interlocking and a single clear and lock relay at each possible entrance to the interlocking to lock up any established route originating at that entry point and to enable the clearing of the proper signal authorizing the train to traverse the established route.
Yet another object of the invention is a route type interlocking control system for railroads in which a single route request relay serves both directions for each track routing, a single clear and lock relay serves all routes originating at each entry location, and separate route cancellation controls are provided for the approach clear and occupied conditions of the established route.
Other objects, features, and advantages of my invention will become apparent from the following specification when taken in connection with the accompanying drawings and appended claims.